Tranexamic acid, or trans-4-aminomethylcyclohexanecarboxylic acid: ##STR4## is used clinically as an antifibrinolytic drug. The trans-isomer is biologically active, while the cis-isomer is practically inactive. The normal route of administration of tranexamic acid is by oral administration, but it can also be administered parenterally, by infusion or by injection. However, because of the limited absorption of tranexamic acid when administered by the oral route--normally 35-40% of administered tranexamic acid is absorbed--fairly high dosages must be prescribed, typically from about 3 to about 6 grams per 24 hours. Such a large intake causes in some patients undesired side effects in the gastro-intestinal tract, probably due to local irritation caused by not absorbed drug.
There is a need for orally active antifibrinolytic drugs with improved absorption properties after oral administration and with reduced undesired gastrointestinal effects. The present inventions provides novel esters of tranexamic acid which possess such properties.